Douglas Anderson 1dbc979172 dt-bindings: drm/bridge: ti-sn65dsi86: Document no-hpd ... The ti-sn65dsi86 MIPI DSI to eDP bridge chip has a dedicated hardware HPD (Hot Plug Detect) pin on it, but it's mostly useless for eDP because of excessive debouncing in hardware. Specifically there is no way to disable the debouncing and for eDP debouncing hurts you because HPD is just used for knowing when the panel is ready, not for detecting physical plug events. Currently the driver in Linux just assumes that nobody has HPD hooked up. It relies on folks setting the "no-hpd" property in the panel node to specify that HPD isn't hooked up and then the panel driver using this to add some worst case delays when turning on the panel. Apparently it's also useful to specify "no-hpd" in the bridge node so that the bridge driver can make sure it's doing the right thing without peeking into the panel [1]. This would be used if anyone ever found it useful to implement support for the HW HPD pin on the bridge. Let's add this property to the bindings. NOTES: - This is somewhat of a backward-incompatible change. All current known users of ti-sn65dsi86 didn't have "no-hpd" specified in the bridge node yet none of them had HPD hooked up. This worked because the current Linux driver just assumed that HPD was never hooked up. We could make it less incompatible by saying that for this bridge it's assumed HPD isn't hooked up _unless_ a property is defined, but "no-hpd" is much more standard and it's unlikely to matter unless someone quickly goes and implements HPD in the driver. - It is sensible to specify "no-hpd" at the bridge chip level and specify "hpd-gpios" at the panel level. That would mean HPD is hooked up to some other GPIO in the system, just not the hardware HPD pin on the bridge chip. [1] https://lore.kernel.org/r/20200417180819.GE5861@pendragon.ideasonboard.com Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20200507143354.v5.5.I72892d485088e57378a4748c86bc0f6c2494d807@changeid		2020-05-18 19:58:04 +02:00
..
ABI	change email address for Pali Rohár	2020-04-10 15:36:22 -07:00
accounting	doc: cgroup: improve formatting of references	2020-03-02 12:57:03 -07:00
admin-guide	Time(keeping) updates:	2020-04-12 10:13:14 -07:00
arm	docs: arm: tcm: Fix a few typos	2020-02-19 02:42:21 -07:00
arm64	arm64 updates for 5.7:	2020-03-31 10:05:01 -07:00
block	block: Document genhd capability flags	2020-03-12 07:47:22 -06:00
bpf	bpf: lsm: Add Documentation	2020-03-30 01:35:12 +02:00
cdrom	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
core-api	mm: add pagemap.h to the fine documentation	2020-04-02 09:35:29 -07:00
cpu-freq	docs: cpu-freq: convert cpufreq-stats.txt to ReST	2020-03-06 00:01:02 +01:00
crypto	crypto: algapi - make unregistration functions return void	2019-12-20 14:58:35 +08:00
dev-tools	linux-kselftest-kunit-5.7-rc1	2020-04-01 16:11:40 -07:00
devicetree	dt-bindings: drm/bridge: ti-sn65dsi86: Document no-hpd	2020-05-18 19:58:04 +02:00
doc-guide	Documentation: build warnings related to missing blank lines after explicit markups has been fixed	2020-02-05 10:30:03 -07:00
driver-api	dma-buf: Couple of documentation typo fixes	2020-04-21 14:37:51 +02:00
fault-injection	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
fb	fbdev: fbmem: allow overriding the number of bootup logos	2020-01-03 14:27:40 +01:00
features	documentation: vm: Advertise support for pte_special in riscv	2020-02-19 02:41:01 -07:00
filesystems	A handful of late-arriving fixes for the documentation tree.	2020-04-10 17:53:43 -07:00
firmware_class
firmware-guide	Documentation: firmware-guide: ACPI: fix table alignment in namespace.rst	2020-04-08 14:27:48 +02:00
fpga	Documentation: fpga: dfl: add descriptions for thermal/power management interfaces	2019-10-16 19:18:26 -07:00
gpu	drm: Nuke mode->hsync	2020-04-29 18:44:26 +03:00
hid	docs: add some documentation dirs to the driver-api book	2019-07-15 11:03:02 -03:00
hwmon	docs: hwmon: Update documentation for isl68137 pmbus driver	2020-03-22 16:42:54 -07:00
i2c	i2c: convert SMBus alert setup function to return an ERRPTR	2020-03-10 12:19:52 +01:00
ia64	docs: add SPDX tags to new index files	2019-07-15 11:03:03 -03:00
ide	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
iio	docs: add some documentation dirs to the driver-api book	2019-07-15 11:03:02 -03:00
infiniband	Documentation/infiniband: update name of some functions	2019-09-13 16:55:55 -03:00
input	Input: docs: fix spelling mistake "potocol" -> "protocol"	2019-08-06 11:24:49 -06:00
isdn	isdn: capi: dead code removal	2019-12-11 09:12:38 +01:00
kbuild	kbuild: support LLVM=1 to switch the default tools to Clang/LLVM	2020-04-09 03:18:21 +09:00
kernel-hacking	docs: locking: Drop :c:func: throughout	2020-03-20 17:16:24 -06:00
leds	leds: core: Add support for composing LED class device names	2019-07-25 20:07:52 +02:00
livepatch	livepatch: Documentation of the new API for tracking system state changes	2019-11-01 13:08:24 +01:00
locking	Documentation/locking/locktypes: Minor copy editor fixes	2020-03-28 12:47:34 +01:00
m68k	docs: README.buddha: convert to ReST and add to m68k book	2019-07-31 13:30:10 -06:00
maintainer	Add a maintainer entry profile for documentation	2020-01-24 09:48:39 -07:00
media	media updates for v5.7-rc1	2020-03-30 13:42:05 -07:00
mhi	docs: Add documentation for MHI bus	2020-03-19 07:41:04 +01:00
mips	docs: mips: remove no longer needed au1xxx_ide.rst documentation	2020-03-24 15:53:48 +01:00
misc-devices	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2020-04-01 14:47:40 -07:00
netlabel	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
networking	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next	2020-03-31 17:29:33 -07:00
nios2	docs: nios2: add it to the main Documentation body	2019-07-31 13:31:51 -06:00
nvdimm	docs: nvdimm: use ReST notation for subsection	2020-01-24 09:54:42 -07:00
openrisc	openrisc: configs: Cleanup CONFIG_CROSS_COMPILE	2020-01-31 22:10:58 +09:00
parisc	docs: parisc: convert to ReST and add to documentation body	2019-07-31 13:30:15 -06:00
PCI	pci-v5.7-changes	2020-04-03 14:25:02 -07:00
pcmcia	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
power	Merge branches 'pm-core', 'pm-sleep', 'pm-acpi' and 'pm-domains'	2020-03-30 14:46:58 +02:00
powerpc	powerpc updates for 5.7	2020-04-05 11:12:59 -07:00
process	Documentation/changes: Raise minimum supported binutils version to 2.23	2020-04-09 00:02:00 +09:00
RCU	doc: Add rcutorture scripting to torture.txt	2020-02-27 07:03:14 -08:00
riscv	It has been a relatively quiet cycle for documentation, but there's still a	2020-01-29 15:27:31 -08:00
s390	Documentation/s390: remove outdated debugging390 documentation	2019-08-21 12:41:43 +02:00
scheduler	Documentation/scheduler: fix links in sched-stats	2019-10-29 04:35:41 -06:00
scsi	SCSI misc on 20200402	2020-04-02 17:03:53 -07:00
security	docs: prevent warnings due to autosectionlabel	2020-03-20 17:01:29 -06:00
sh	docs: remove extra conf.py files	2019-07-17 06:57:52 -03:00
sound	ALSA: hda/realtek - Remove now-unnecessary XPS 13 headphone noise fixups	2020-03-31 10:54:06 +02:00
sparc	docs: add arch doc directories to the index	2019-07-15 11:03:01 -03:00
sphinx	docs: Fix empty parallelism argument	2020-02-25 03:11:04 -07:00
sphinx-static	doc-rst: Reduce CSS padding around Field	2019-10-02 10:03:06 -06:00
spi	spi: docs: convert to ReST and add it to the kABI bookset	2019-07-31 14:13:13 -06:00
target	docs: prevent warnings due to autosectionlabel	2020-03-20 17:01:29 -06:00
timers	docs: add some directories to the main documentation index	2019-07-15 11:03:03 -03:00
trace	New tracing features:	2020-04-05 10:36:18 -07:00
translations	media updates for v5.7-rc1	2020-03-30 13:42:05 -07:00
usb	usb: gadget: add raw-gadget interface	2020-03-15 11:34:48 +02:00
userspace-api	docs: userspace: ioctl-number: remove mc146818rtc conflict	2020-02-13 11:42:02 -07:00
virt	ARM:	2020-04-02 15:13:15 -07:00
vm	mm/zswap: allow setting default status, compressor and allocator in Kconfig	2020-04-07 10:43:41 -07:00
w1	docs: w1: Fix a typo in omap-hdq.rst	2019-12-30 11:58:02 -07:00
watchdog	linux-watchdog 5.4-rc1 tag	2019-09-27 11:17:38 -07:00
x86	Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2020-03-31 11:04:05 -07:00
xtensa	docs: add arch doc directories to the index	2019-07-15 11:03:01 -03:00
.gitignore	.gitignore: add SPDX License Identifier	2020-03-25 11:50:48 +01:00
asm-annotations.rst	Documentation: Call out example SYM_FUNC_* usage as x86-specific	2020-01-16 12:53:16 -07:00
atomic_bitops.txt
atomic_t.txt	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-07-08 16:12:03 -07:00
bus-virt-phys-mapping.txt
Changes
CodingStyle
conf.py	docs: conf.py: avoid thousands of duplicate label warning on Sphinx	2020-03-20 17:01:34 -06:00
COPYING-logo	docs: logo.txt: rename it to COPYING-logo	2019-07-15 09:20:27 -03:00
crc32.txt
debugging-via-ohci1394.txt
digsig.txt
DMA-API-HOWTO.txt	docs: DMA-API-HOWTO.txt: fix an unmarked code block	2019-07-15 09:20:24 -03:00
DMA-API.txt	dma-mapping: remove dma_release_declared_memory	2019-09-04 11:13:19 +02:00
DMA-attributes.txt	dma-mapping: remove the DMA_ATTR_WRITE_BARRIER flag	2019-11-14 12:01:54 -04:00
DMA-ISA-LPC.txt
docutils.conf
dontdiff	modpost: dump missing namespaces into a single modules.nsdeps file	2019-11-11 20:10:01 +09:00
futex-requeue-pi.txt
hwspinlock.txt	hwspinlock: add the 'in_atomic' API	2019-06-29 21:08:14 -07:00
index.rst	Char/Misc driver patches for 5.7-rc1	2020-04-03 13:22:40 -07:00
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
Kconfig
kprobes.txt
kref.txt	docs: kref: Clarify the use of two kref_put() in example code	2020-02-25 03:39:10 -07:00
logo.gif
lzo.txt
mailbox.txt
Makefile	Kbuild updates for v5.7	2020-03-31 16:03:39 -07:00
memory-barriers.txt	Documentation/memory-barriers: Fix typos	2020-02-27 07:03:14 -08:00
nommu-mmap.txt
percpu-rw-semaphore.txt
pi-futex.txt	docs: locking: convert docs to ReST and rename to *.rst	2019-07-15 08:53:27 -03:00
preempt-locking.txt
rbtree.txt	docs: rbtree.txt: fix Sphinx build warnings	2019-07-15 09:20:24 -03:00
remoteproc.txt	remoteproc: Add elf64 support in elf loader	2020-03-25 22:29:40 -07:00
robust-futex-ABI.txt	threads: Update PID limit comment according to futex UAPI change	2020-03-21 17:48:13 +01:00
robust-futexes.txt
rpmsg.txt
speculation.txt
static-keys.txt
SubmittingPatches
tee.txt	Documentation: tee: add AMD-TEE driver details	2020-01-04 13:49:51 +08:00
this_cpu_ops.txt
unaligned-memory-access.txt
xz.txt